Evaluation of Breath-Holding Test in Assessment of Peripheral Chemoreflex Sensitivity in Patients with Chronic Heart Failure.

Nikita Trembach,Igor Zabolotskikh

doi:10.2174/1874306401711010067

Abstract

Background:The sensitivity of peripheral chemoreflex is a marker of the severity of heart failure and the prognosis of the outcome in these patients. The assessment of chemosensitivity in these patients remains an actual problem.Objective:The aim of the study was to explore the relationship between a Breath-Holding Test (BHT) and single-breath carbon dioxide test and to evaluate the reliability of both tests in patients with Heart Failure (HF).Method:The study was performed in 43 patients with chronic heart failure. All subjects underwent BHT and single-breath carbon dioxide (CB-CO2), the evaluation of both tests was repeated a month later. Relationship of two test was evaluated by correlation analysis. Reliability was assessed with calculation of Standard Error of Measurement (SEM), Coefficient of Variation (CV) and Intraclass Correlation Coefficient (ICC).Results:The duration of the breath-holding was inversely correlated to the result of CB-CO2 test (r = -0.86 at first measurement and r = -0.79 after a month) The ICC was 0.87 (95%CI: 0.78–0.93) for SB-CO2 test and 0,93 (95%CI: 0.88–0.96) for BHT, the CV was 24% for SB-CO2 and 13% for BHT. SEM for SB-CO2 test was 0.04 L / min / mmHg and limits of variation was 0.11 L / min / mmHg; SEM for BHT was 3.6 sec and limits of variation was10 sec.Conclusion:Breath-holding test is a reliable and safe method for assessing the sensitivity of peripheral chemoreflex to carbon dioxide in patients with heart failure.

Highlights

The problem of impaired sensitivity of peripheral chemoreflex in patients with chronic cardiorespiratory diseases has given increased attention in the recent decades
The duration of the breath-holding was inversely correlated to the result of CB-CO2 test (r = -0.86 at first measurement and r = -0.79 after a month) The Intraclass Correlation Coefficient (ICC) was 0.87 (95%CI: 0.78–0.93) for SB-CO2 test and 0,93 (95%CI: 0.88–0.96) for Breath-Holding Test (BHT), the Coefficient of Variation (CV) was 24% for SB-CO2 and 13% for BHT
Earlier studies indicated that activation of the local angiotensin II system [3, 4] and a decreased neural nitric oxide synthase–nitric oxide pathway [5, 6] in the carotid bodies are associated with chemoreceptor hyperactivity during progression of Heart Failure (HF)

Summary

Introduction

The problem of impaired sensitivity of peripheral chemoreflex in patients with chronic cardiorespiratory diseases has given increased attention in the recent decades. Earlier studies indicated that activation of the local angiotensin II system [3, 4] and a decreased neural nitric oxide synthase–nitric oxide pathway [5, 6] in the carotid bodies are associated with chemoreceptor hyperactivity during progression of HF It was observed, that decreased blood flow in carotid bodies contributes to chemoreflex dysfunction [7]. An increase in the afferent flow from the peripheral chemoreceptors leads to an increase in sympathetic tone due to stimulation of the autonomic centers in the medulla oblongata [8] and hypothalamus [9] These disorders lead to an increased risk of cardiac adverse events and a poor outcome in patients with HF. The assessment of chemosensitivity in these patients remains an actual problem

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Results

Discussion

Conclusion